Soil acidity levels for blackberry liming recommendation and yield increase

Abstract

The objective of this work was to determine the acidity levels to obtain adequate soil chemical attributes for the maximum fruit yield of blackberry trees grown in acidic soils subjected to increasing limestone rates. The BRS Tupy, Brazos, Guarani, and BRS Xavante blackberry cultivars were evaluated on the Typic Hapludox (LVdf) and Rhodic Hapludox (LVd) soils, to which four rates of dolomitic limestone were applied (0, 1.5, 3.0, and 6.0 Mg ha^-1). The effect of liming on soil chemical attributes, in a 2×4 factorial arrangement (soils and limestone rates), as well as leaf nutrient content and fruit yield, in a 2×4×4 factorial arrangement (soils, limestone rates, and cultivars), were evaluated. The maximum fruit yield was obtained with 3.3 Mg ha^-1 dolomitic limestone. The blackberry cultivars showed a high demand for Ca, Mg, and base saturation and a low tolerance to aluminum in the soils. From 3.3 Mg ha^-1 dolomitic limestone, the maximum fruit yield of blackberry trees grown in acidic soils is obtained with pH 5.6, maximum tolerated aluminum saturation of 6%, Ca and Mg concentration of 45.3 mmol_c kg^-1, and base saturation of 48.3%.